I have the BTT-370 which didn't include the wireless transmitter or receiver (FX-71). I find dozens of the old style FX-65 but the transmitter is too fat and will not fit into the back of the Blu-ray player. I found one on Amazon.com in the UK but I'm in the states so the power cord would be different then there's the matter of shipping. Now, I've found an FX-71 RECEIVER used for a very good price, but it's useless without the FX-71T, ("T" for transmitter). I can't imagine why these are so impossible to come by. It's a 2011 HTIB and is a name brand. Had I known it would have been this hard to upgrade I would have bought Samsung. HELP!